the choices we all have to make. what we wrestle inside our head. will we choose love or lust? to tell the truth or lie? when what we choose could lead to a dream or a nightmare? >> tonight, we unlock the secrets of your mind. why we do what we do. why we kill. a revealing journey into the mind and heart of darkness. we go face to face with a serial killer. so, what if i called you something that you didn't like? >> you die. >> a psycho path wired differently than the rest of us? plus, an evil turn what drove this family man to kill the ones he loved? an unprecedented look literally

inside the brain of star wrestle ler chris benoit, what made this good mind go bad? and what would you do if you were an upstanding member of society and you discovered that you may have the mind of a murderer? several notorious killer -- >> is this man a natural-born killer? >> reporter: they were all innocent children. a son. a brother. lives with limited possibilities ahead of them. but, what these boys would grow up to become, brutal killers. could their brains have provided a road map to the sickness that would consume them? >> every mean, vicious psycho path was an innocent young baby,

for some people, dyes are cast early in life. >> recent research suggest that it's evidence in the brain. those who killed over and over may have been born to do so. >> only recently of je in theics that we have been able to peer into the minds of murderer. >> reporter: we began our exploration along a remote road in texas. headed to death row. where i sat down with a 45-year-old who could have one of the baddest brains in america. >> the first time i did a shot of done, it was the best feeling that i ever had in my life. and the first time i killed somebody, it was such a rush, and, it was just like that shot of done, every time i did it, it was that rush again. and i started chasing that high.

>> reporter: tommy was once a little boy growing up in st. louis. around the age of 14, he said he became addicted to killing. how many people have you killed? >> lord, i don't know. i don't know. >> reporter: 10? >> yeah. >> reporter: 20? >> probably. >> reporter: 30. >> it's thereupon. >> reporter: 50. >> see, i'm not -- billy the kid making matches on my holser the. so, i know it's been a lot. >> psycho paths are individuals who lack conscience, remorse, they lack guilt, that's one of the reasons they terrorize society so much. >> reporter: he's on death row for one murder, but he's linked to at least 17 more. the drifter's lifestyle helped

him elude policeman for 15 years. as victims turned up from coast to coast. >> i am hatred. >> reporter: when i look at you, i look at hate. >> i don't know what love is. two words that i don't like to use is love and sorry. because i'm about to hate. >> reporter: he raped many before cutting their tloets. stabbing some. >> vicious cycle. >> reporter: i couldn't help but grateful for the glass between us. >> i have no feelings no more. no emotion. >> they showed zblsh this doctor has studied the brains of people scientifically determined to be psychopaths. >> one of the key difference in the brains of psychopath there's

a structural impairment to part of the brain, this is a part of the brain very much involved in the generation of emotion. it was structurally deformed in the psychopaths. >> i like to watch the eyes fade. the pupil fade. >> reporter: what do you like about that? >> it's just like, setting your soul free. >> just don't have those normal feelings of disgust. >> the last images of the family. >> reporter: one crime cell confessed shows the disregard of human life typical of psychopaths. a 37-year-old mother, pregnant at home with her 3-year-old son, both bludgeoned to death. what are you thinking and feeling when you kill someone? >> it's just like that drug, i'm after that drug again.

i don't have have an on/off switch. i'm just after that drug, i'm after that feeling. >> reporter: during the beating, she went into spontaneous labor, giving birth to a daughter, who investigators believe to be alive at the time. the new baby was also beaten to death and the body of her husband turned up a day later. shot three times in the head. i wonder if you could just tell me what happened as you were killing her, did she give birth to a baby? >> you know, you're pushing your luck. >> reporter: i'm sorry. >> let's not get -- let's not get into blood and guts. because that's what you're trying to get into. >> reporter: he blames much of his murder rage, to abuse that he suffered as a child. you also killed children?

why would that happen? >> i didn't want them to live through the pain i lived through. >> reporter: it's biology plus environment. it's biology coming together with environmental insults which raise the odds of an individual becoming a violent criminal offender. >> this door right here -- >> reporter: two days after his final murder, he walks police through the crime scene. >> we stayed up little and we got into a fight where we were going to sleep. we talked about at the time, britney spears. >> reporter: crystal sells, 10 years old at the time, was sleeping over at her friend's house. a decade later, that night is still fresh in her memory. >> i woke upstartled a little

bit. and, out of nowhere, i was kind of confused, to a loud noise. >> i woke this girl up. >> reporter: her friend, katie, was asleep on the bottom bunk. >> i kind of just leaned my head up a little bit. i could see that there is this scary, older man that i have never seen before. >> she like jumped back. and i cut like this right here. >> reporter: >> he had a hand on her mouth and her neck. and she's looking at me, he cut her throat and she fell down to the ground. i heard katie, on the floor at the bottom of the bunk bed, she was like gasping for air and choking. like, she couldn't breathe. >> reporter: 13-year-old katie harris lay dying on the floor. >> he was about to shut off the light. he looked one last night and he

noticed that i was there. he didn't hesitate at all. came back towards me with the knife >> i went like this. >> the only thing he said was move your hands. he reached over the top bunk and cut my neck. >> reporter: he sliced crystal's neck, severing her wind pipe. >> i am very sure that he killed me. >> reporter: crystal eidentifie as her assailant and friend's killer. putting an end to his homicide spree. >> reporter: do you remember the little girl who survived? >> yes, there's not a day that goes by that i don't think about her. >> reporter: what did you do to her, sir? >> her neck was cut. >> reporter: how did you do that? >> with a knife. >> reporter: do you have anything to say to her the little girl who survived? >> i guess, you'll relay this

message, too. >> it's very difficult to control a psychopath. they're the person in control. in an interview, psychopaths tend to take control of the interview. >> what's your name. >> reporter: martin. >> martin? >> reporter: yes. can i call you tommy? >> without a doubt. i don't think she really wants to hear what i got to say. >> reporter: what did you see in his eyes? >> to be honest, he seemed blank. i mean, there was no emotion. it wasn't hard for him. all he would say, move your hands. it was just -- i mean, after what i had seen him do, he had no emotions in his eyes. >> reporter: that emptiness evident as we spoke. what if i called you something that you didn't like, would you think about killing me? >> if we were in a fight, you'll

get your head down in the concrete, then, so be it. >> reporter: what happens when my head goes down to the akron crete? >> what do you think happens? it cracks like a coconut. >> reporter: and then what happens? >> you die. >> announcer: when we come back -- wired to kill? can you see a murderous impulse in the brain? this confessed killer wanted to find out? that's after the break. set. and the cast has been gathered. when the curtain rises. and the spotlight is yours. having a strong signal at your back... is like having invisible power everywhere. because in that moment... you're not there to take up space. you're there to fill the room. rule the air. verizon. right now, buy a blackberry smartphone and get a second one free. like the bold. only at verizon.

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you don't grow up wanting to be locked away forever, being a mass murderer. you grow up being a ballplayer, race car driver, fireman, things like that. i don't knwant to know what

happened. >> reporter: joe confessed to the murders of 17 women. what caused this man to kill? he believes it all started in his brain. >> apparently, i have a deficit in this frontal lobe area, and my thought process is not your thought process. >> reporter: so, he's allowed cutting-edge science to explore his brain in the hopes of finding answer to the question that plagues him -- >> nice to meet you. >> reporter: why does he kill. i visited with the 51-year-old inmate in an upstate new york prison. >> one of the earliest homicides might have been euphoric. >> you never get that original rush. you keep chasing it. >> reporter: the killing began on a winter night in 1989, after rifken picked up a prostitute. >> as the night progressed, i'm

about 150. >> reporter: you haven't seen any sex at all sf. >> no. within the next couple of hours, i got fed up and i started hitting her. basically, beat her until my arms got tired and we wrestled on the floor and i ended up strapgling her. i'm starting to realize that, i had done something that, you know, this is not -- this is not good. this is extremely screwed up. >> reporter: not screwed up enough to stop him from a clean-out process nearly as grotesque as his crime. >> i cut her up with a knife. >> reporter: you started severing the body? >> yes, made it as small as it could -- basically, i cut everything to the joint and popped the joints out. the legs the same way.

proceeded to take her head off. so, now, i had six pieces that i wrapped up and carsuallied loadd into the trunk of the car. >> reporter: how someone act casually? neurorow scientist analyzeized his brain scan. >> i thought to myself, this is a brain that's vulnerable to violence. he had low activity in his prefro prefrontal cortex. >> reporter: say for example in these scans, the normal of the normal brain is brighter in the front. in the murderous brain, that same region is dark. >> the area they call the frontal lobe. >> in its simplest form that's where we have the conscience. >> reporter: do his scans show he's missing conscience?

played a role in the brutal murders of so many women? >> there were good nights with prostitutes. bad nights with prostitutes. times you get ripped off. >> reporter: he committed his time murder in june 1993. >> she was the third, fourth girl that i was with that night. in the backseat of the car, strangled her. drove her home. >> reporter: he wrapped up her body and stuck her in the trunk before turning the car over to his mom. >> none of it made sense by that time. >> reporter: he told me that he later transferred the decomposing body to the back of the family pickup truck, but on the highway, a license plate happened to fall off. and he was stopped by the police. >> troopers discovered that there was a body of a female, a white female n the back of the

pickup >> i was under arrest. i adopt know. i knew that that was it. >> what do you have to say? >> psychopaths know right from wrong but they don't have the feeling for what's right and wrong. >> reporter: dr. adrian reign has studied psychopaths for 30 years, they both believe while the pie sewpath brian can't be cured, it can be treated. omega3. >> omega3 given to young prisoners and have shown after about four months of omega-3 treatment, there's about 30% reduction in serious -- we can stop the rot. >> reporter: early intervention could be the key. >> the sad thing is, if i would have seen him perhaps as a

teenager and helped him remediate his brain, that he would have been less likely, i think, to act out in violent ways. >> reporter: do you think if you had an intervepgs when you were younger, you might not have done what you did? >> well, you know, this is what they could have seen when i was 8 or 10. maybe none of this would have happened. maybe i could have gotten the therapy or drugs i needed. >> reporter: maybe some people would have survived. >> yeah, and maybe now the next kid who comes along. >> reporter: this discussion has spargd an explosive legal debate. if these killers have bad brains, did that excuse their action. >> brain imagery research will be used to exonerate psychopath murderous individuals, that should be put to death or locked up for life. >> reporter: it's been coined

neurorow law. in fact, reign testified in the capital murder case of a young man from a troubled home. >> we found that he had much function in the part of the brain controlling and regulating behavior. put all of the facts together the abuse, poverty, together with the poor brain functioning, and he's a walking recipe for later violence. >> reporter: he was sparred the death penalty in part because of his brain scans. is that the right decision? >> if we buy into the line of thinking that i put forward to the judge and jury, then, is this is a slippery slope to armageddon. >> reporter: this is just making excuses for behavior, trying to

find the answer in the brain is a sfophisticated way of excusin your behavior? >> that's their opinion. it gives me part of answer. it's not the complete answer. was i destined to do what i did? i don't know. >> announcer: up next, can a good brain go bad? what could cause this world-class family man and wrestler to killer the ones he loved? wrestleryou guys r the ones he thank you for noticing. it's a good snack. you're welcome. they grow so fast. [ woman ] i know. they do, don't they? why is carol sitting all the way over there? carol almost told evan that there are vegetables in the chef boyardee. nearly ruined their favorite after-school snack. so she's in a time-out. i hope she learns from this. [ female announcer ] chef boyardee

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he was a loving father. >> i wished i would have known my son. >> announcer: and world-class wrestler, and then he did the unthinkable. >> the wife was bound on her feet and also on her wrist. >> announcer: a stunning turn that left many asking, what made this good brain

>> reporter: he was a powerhouse in the ring. a man at the height of his strength. world-famous wrestler. champion to his fans. his father says that he always wanted to be a wrestler. >> he was pretty much driven from the age of 12, 13 to get into the wrestling industry. chris lifted weights every day. he was breaking records in high school. in our basement. >> reporter: when he became a pro wrestler at 18, his career soon skyrocketed. by the age of 25, he was already a world champion. >> he won titles every place that he traveled in the world.

>> reporter: while living the wrestling high life, chris benoit was a devoted dad and husband, who cherished time with his family. >> i wished you would have known my son when he was the chris benoit. he loved to be at home. playing with his children. that's where he wanted to be. >> reporter: in june 2007, mike benoit's heart was broken. behind the doors of this suburban atlanta home, an unimaginable horror. >> the wife was bound on her feet and i think, also on her wrist. >> reporter: chris benoit strangled his wife nancy and suffocated their 7-year-old son daniel. bibles were found next to their bodies. >> there was a bible beside each of the body of the victims. >> reporter: his own body was

found hanging in the basement. he had killed himself. >> we're ruling it as a double homicide-suicide. >> reporter: at some point, during the tragic weekend, investigators reported that benoit did internet searchers on the prophet elijah. one of the stories of elijah is how the prophet could raise a boy from the debt starting with placing the dead child on a bed. police found young daniel on his own bed. >> he seemed like a really nice guy. >> reporter: the violent deaths stunned and confused every who knew him. >> the next three, four days were an absolute nightmare. i watched tv 24 hours a day. wait i waiting for someone to say something nice about my son. it wasn't happening. everything was bad. >> reporter: chris benoit, at just 40 years old, seemed to

have it all. >> he wanted to stay home. come on, go out and have dinner at the restaurant. no, i want to stay home and spend time with the family. >> reporter: upon learning about the chris benoit's case, researchers, who had been examining of deseeszed pro football players, were eager to study his brain. >> i'm not certain about his behavior and what caused it. we can only say that he had very similar changes and he had a neurorow behavior that was similar to what we saw in others. >> reporter: pounded. slammed. with chairs and ladders. >> hard-core wrestling. tables, ladders, chairs. props that they were using. when they getting hit in the head with a chair, out's a real

chair. >> reporter: neurologyists one suffers three or four more concussions is likely to have long-time damage to the brain. >> when i asked my son how many he had had, he said to me, dad, i don't count them anymore. i have had so many. ? the investigation has zeroed in on steroid. >> reporter: the intense media coverage was focused on steroid rage. when benoit tested for steroids. >> i don't think that 'roid rage, maybe a snap in judgment, a snap in emotions or actions, i don't think this is what explains chris' behavior. >> still today what they talk about is steroid. they talk about the 2007 murder

of his wife and his son. 'roid rage. what scientific evidence do people have? >> reporter: mike benoit decided to turn over his son's brain to scienti scientists. >> they took chris's brain tissue and actually examined it. >> reporter: when we come back. boss: our breakout session is gonna be great. got the gecko t-shirt... "4 mllion drivers switched!" gecko water bottle... notebok... chamois... gecko: sir, i feel a little bit uncofortable with all...

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>> reporter: the hee us now crime shocked those who knew him. chris benoit murdered his wife and young son, then killed himself. >> everything that he did for a period of 22 years in the ring, he was a very accomplished wrestler. he won titles every place that he traveled in the world. in three days, he destroyed -- he destroyed that image. >> reporter: in the hope of understanding why, a mystified father allowed scientists to study his son's brain. dr. bales and doctor bennett omalu cut sections of benoit's brain. they examined the brain tissue under a microscope.

what they said they found, evidence of repeated blows to the head. >> very smooth. >> reporter: in chris benoit, an unnormal pro teen that indicates severe brain damage. >> these areas here, of brown staining, all areas of dead nerve cells other dead neurons. >> his damage was extpsive. it was replete across multiple areas of the brain. it was remains one of the worse we have seen. >> reporter: starting with pittsburgh steelers hall of famer mike webster, who dissolved into a shell of a former self after retiring at just 38 years old. >> i knew mike very well

personally, saw mike who was a great player, a great father, a great teammate, a great person. change >> i slept in the car for probably about a year and a half out of the last five years. >> mike died homeless. pitiful. he had a few close friends. >> reporter: dr. omalu suspected the bizarre behavior that marked the end of webster's life could be explained in his brain, caused by repeated blows to the head. it was chronic traumatic encephalopathy. >> lot of these repeated blows are part in the brain. >> reporter: they expected to rename it mike webster's disease.

>> dr. bailes said that webster and benoit's brains were simi r similarly damaged. >> the changes in the brain were microskoply very similar. they both had extensive disease. >> reporter: could the disease be the reason that chris benoit was driven to kill? what did they tell you about your son's brain? >> that it was -- it was heavily, heavily damaged. i still get emotional about it. we now had a good understanding of why the tragedy had taken place. we now knew that our son had a serious amount of brain damage. >> reporter: mike benoit also thinks that's why his son was suffering insomnia, mood swings and depression before it happened. >> he was on a collision course that something terrible was

going to happen. you could look at his life and see him going downhill. a number of changes that took place over a period of time. chris had become an extremely religious person. he read the bible on a daily basis. could quote scripture. that's not chris benoit. >> reporter: is it common that individuals with this kind of injury develop a relidges youty? >> in some cases it has been a at any rate. >> reporter: how does he go from a man who loves his family to murdering them? >> i don't think we can come up with why human behavior can become severe and so perverse and so extreme. >> reporter: but for one father, his son's dream of becoming a wrestler turned into a nightmare. >> i think if chris benoit had been anything other than a

professional wrestler, we wouldn't be sitting here having this conversation. the awwe vehemently disagrees with this position and questions the scientific findings on chris benoit. the head trauma could quote be t cause the son's behavior is impossible. what would you say to some who argue, when you place the blame for these actions on brain damage, you're basically making an excuse? >> absolutely. that's what people talk about. what's their excuse? i would like people to have an understanding that the tragedy that took place in 2007,

happened because of his career choice. >> reporter: does that mean that wrestling and its impact on your son, turned him from a good man into a bad man? >> absolutely. no question. >> announcer: what would you do if you discovered you may have a brain of a killer? >> reporter: were you shocked? >> i was shocked. i was looking an explanation. >> announcer: when we come back. ? yes, i hear progressive has lots of discounts on car insurance. can i get in on that? are you a safe driver? yes. discount! do you own a home? yes. discount! are you going to buy online? yes! discount! isn't getting discounts great? yes! there's no discount for agreeing with me. yeah, i got carried away. happens to me all the time. helping you save money -- now, that's progressive. call or click today. ♪ call on me, brother ♪ when you need a hand

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>> reporter: don't let the scooter fool you. this neuroscientist is a master at identifying the brain of a killer. >> here's the comparison of a normal scan and some murderers. >> reporter: give him several random brain scans and he'll spot the murderer every time. his reputation is such that even hollywood has tapped his expertise. >> the five brains that we identified all had damage in the orbital cortex, right above the eyes. >> reporter: but for dr. fallon his research has take an shocking hollywood turn in all of its own. veering from the professional to the personal. >> when i was in college,

growing up, kind of a dark side to you. i said, but i don't do anything bad. it doesn't matter. >> reporter: it all started innocently enough, during a conversation with his mother. >> i said, you know jim, why don't you look into your family background while you're studying these criminal minds. because i had heard through the years, being married to his father, that there were many murderers in the family. >> when she said check your father's side of the family, with a wink -- >> reporter: what did you discover? >> there were several notorious killers -- >> reporter: in your direct line? >> direct father's line. >> reporter: fallon is a dissident of the famous cornell family, founders of the ivy league university. they had an alarming penchant for homicide.

six by fallon's own count. the last in line of the murders was a cousin, who inspired a haunting and instantly recognizable nursery rhyme. she was accuseded of murdering both her mother and stepfather. but, here's you, studying other murderers, suddenly discovering that your own lineage is littered with them, what was your reaction. >> frankly it was coo uppkind o. it got me to thinking, what if it was us? >> reporter: he analyzed brain scans of his mother, his wife, siblings and even his children. >> and everyone looked normal.

>> reporter: everybody was cl r clear. >> one of the p.e.t. scans showed a very abnormal pattern, it showed that there was almost no activity in this person's orbital cortex, it looked like at all of these murders. who was it? it was mine. >> reporter: it was yours? >> it was mine. >> reporter: unlike the rest of his family, he remarkably low activity in his orbital cortex, that acts as a break on impulsive behavior. also abnormal in the brains of murderers. >> reporter: were you shocked? >> i was a bit concerned about it. and i was a bit shocked. i still was looking for an explanation. >> reporter: fallon then followed up his brain scan study with a thorough examination of his own family's dna. once again the results were

startling. >> one person had all of the high-risk forms of genes known as warrior genes. it turned out to be mine. >> reporter: looking at these two, i should be a problematic. >> reporter: but here we are, you got the genetic inheritance, a brain that appears to function like a murderer's brain, but you haven't committed any murders. you never really hurt anybody? >> no, i'm peaceful. >> reporter: this dark realization threw his entire world into question, he believed that psychopaths may be wired to kill. so, why hasn't he out murdering people? does that mean that thesis is wrong? >> it could be the idea that the thesis is wrong or some other

mitigating factor. a lot of love and nurturing, that neutralized this bad biology. >> reporter: unlike my homicidal psychopaths, he had a childhood filled with love and encouragement. surrounded by a large and supportive family. >> >> did you dote on him? >> i don't think so. he was so adorable, we just loved him. maybe we dote on him, i don't know. >> a large family. we all had great fun. >> reporter: fallon raised married his high school sweetheart. as you were growing up, did you ever feel that your dad was -- i don't know -- angry, impatient? was he ever difficult towards you in.

>> he was never difficult. there wasn't violence. >> reporter: the same biological patterns that may make a psychopath make minutive, violent, in fallon, a impulsive family man. >> they really liked our parents. >> he says it's his environment that may have made all of the difference. he said what he learned about his brain and his own genetics, means that he didn't have such a loving family, he might well have gone on to do some very bad things. what's your reaction to that? >> well, i guess i am glad i was good to him. >> reporter: if you didn't have that environment, given what you know about your brain and

genetics that in all likelihood that you may have gone on to do something criminal. >> i think so. an honest answer, i believe i would have had a much, much different outcome as an adult. loving people back has to be the greatest gift that we have, is the ability to do that. it seems to overcome all the ability to do that. it seems to overcome all bit says turn right. it says you like soft rock. it says you like cool jams. i do like cool jams. it says you're not real. [ growls ] sorry. it says mackenzie ellerd got that exact same dress.

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[ airplane engine rumbles ] show me the carfax. yeah, show me the carfax. we...we ran out. before you buy a used car, get a carfax report. it's free at thousands of reputable dealers. just say, show me the carfax. next week on secrets of your mind -- a woman's life hangs in the balance. >> it's a dangerous problem that

we're dealing with. bad things can happen any time you do a surgery like this, which includes death, which includes e irreversible brain damage, which includes stroke. in this situation, our backs are against the wall. >> this lady has a tremendously big blood clot. she's in a deep coma. >> announcer: he has three minutes to save her life. >> that's bad. a rupture like that during surgery of the brain is difficult thing to handle. so, hopefully, we did. i think we did >> it's very hard to work on a baby. >> nothing more daunting as a father myself is then considering passing on your child on to someone op to operate on their brain. >> when it comes to your head,

they're putting little holes in my head and into my brain. that's scary. >> the brain is undoubtedly the most complex structure on the face of the earth. something that we work day and night to try to preserve. >> all right, you're doing good. >> announcer: that's next week, .> all right, you're doing good. >> bay area school board takes a